I got a set of your Caribou cases and racks as soon as they came out for the Ulysses. I have to say that I had very high hopes for this setup and they are better than I imagined. It is really nice to have some lockable storage on the bike and they are so fast and simple to take on and off. I also really like the very narrow profile of the bike with the luggage on ... the factory Ulysses bags are very fat in comparison.
I just got back from a weeklong business trip from Boise, Idaho to Salt Lake City, Utah on the Uly and the bags were great. It rained hard on me once and the bags did not let a drop in.
I take my bike to work as well and use a Pelican 1490 case filled with a laptop computer and some handtools. It currently is riding on the triple tail and secured with a bungee net but a top case would be nice for this task.
Here are a few pics with the bags on the bike so that others can see the Caribous on an orange Uly:
Have you been able to solve the problems with Uly topcase yet? Will it be coming to your website soon?